Downing Street has been warned against sidelining dissent in its handling of the coronavirus crisis, after complaints that Boris Johnson has not hosted a key planning meeting for more than a month. There has not been a gathering of the UK government’s emergency Cobra committee, including the leaders of the devolved nations and the London mayor Sadiq Khan, since 10 May. The last such meeting was held on the day Johnson controversially decided to change his government’s main coronavirus message to “stay alert”. It has led to concerns that No 10 has sidelined Cobra meetings after encountering resistance from his counterparts over the UK-wide response to the pandemic. In an interview with the Observer, the Welsh first minister, said that any attempt to sidestep difficult conversations about the handling of the pandemic would be short-sighted. “I don’t think there is anything wrong with challenging conversations, provided it is done in a constructive spirit,” he said. “The decisions in some ways get trickier as they go along. Lifting lockdown is complex. The case for talking together regularly is actually greater as we all face these challenging decisions.” The concerns come amid accusations that Downing Street stopped England’s chief nurse from attending a daily Downing Street briefing on the coronavirus for refusing to back the lockdown actions of Dominic Cummings. The last Cobra meeting took place on 10 May, when the prime minister laid out his roadmap for dealing with the virus. He announced he was changing the overall advice from “stay at home” to “stay alert” – a move not followed by Scotland and Wales. Previous Cobra meetings have also seen leaders at odds over issues such as face coverings. The devolved nations have since taken slightly different approaches to easing lockdown measures. Drakeford said that the Cobra system had become “ad hoc” and that an invitation to a meeting to review the progress of the pandemic had never materialised. He also warned that the lack of a regular meeting meant there was no “scaffolding you need to make a success of the United Kingdom”. “Up until the last decision point, we were all on a common, three-week decision-making cycle,” he said. “The pattern had been that each three-week cycle had culminated in a Cobra meeting where we understand one another’s decisions. I had simply assumed there would be one at the end of the last cycle, but it just never happened. There was no explanation. “It’s not that if Cobra doesn’t happen, nothing happens. But Cobra had become in this crisis the culminating point.” Khan warned that sidelining the gatherings was a mistake. “Covid-19 is the biggest health and economic crisis we have faced since the second world war – so it is clearly a mistake for the government to exclude regional and devolved leaders from crucial decision-making meetings,” he said. “London, Scotland, Northern Ireland and Wales have a combined population of close to 20 million people as well as control over vital services that need to be coordinated to tackle the virus. It is vital that we have a seat at the table where crucial matters are discussed.” A government spokesperson said the Cobra meeting was not the only forum for UK-wide discussions. “As we begin to roll out test and trace and implement a more targeted local approach to tackling coronavirus, it is crucial that we continue to work closely with the devolved administrations and local authorities,” they said. “The chancellor of the duchy of Lancaster has regular calls with the first ministers and the prime minister spoke to them at the end of last month. The prime minister also recently held a call with the M9 group of mayors. We continue to implement the roadmap laid out by the prime minister last month, when he held a Cobra attended by the devolved administrations.”